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71.
72.
BACKGROUND: The objective of this study is to evaluate the clinicopathological features of incidental renal cell carcinoma, compared with non-incidental carcinoma. METHODS: Between July 1st, 1984 and June 30, 1994, 87 renal cell carcinoma patients were treated at our hospital; 56 had non-incidental renal cell carcinoma and 31 had incidental carcinoma. The clinicopathological features were examined. RESULTS: The incidence of incidental cancer ranges from 0 to 66%, and the incidence has increased in recent years. The median value of maximal tumor size was 4.0cm (1.5 approximately 8.0cm) for incidental cancer, and 8.0cm (3.0 approximately 16cm) for incidental cancer, and 8.0cm (3.0 approximately 16cm) for non-incidental cancer, i.e., the incidental cancer was significantly smaller than the non-incidental one (p < 0.001). The pathological stage of the resected non-incidental renal cell carcinoma (n = 47) was pT1, pT2, pT3 and pT4 in 0, 23, 21 and 3 patients, respectively. For the resected incidental renal cell carcinoma (n = 31) 3, 26, 2 and 0 patients showed pathological stages pT1, pT2, pT3 and pT4, respectively; the pathological stage of incidental renal cell carcinoma was significantly lower than that of non-incidental carcinoma (p < 0.001). Eighteen and 29 resected non-incidental renal cell carcinoma were grades 1 and 2, respectively, whereas 17 and 14 resected incidental renal cell carcinomas were in grades 1 and 2, respectively. Vascular invasion by tumor cells was shown in 31 (66.0%) and 8 (25.8%) patients with non-incidental and incidental renal cell carcinomas, respectively; the incidence of vascular invasion in incidental cancer being significantly lower than in non-incidental cancer (p < 0.001). The performance status and general condition in patients with incidental renal cell carcinoma were superior to those in patients with the non-incidental cancer. The 1, 3 and 5-year survival rate of all 87 renal cell carcinoma patients was 81, 62 and 57%, respectively. These rates for patients with non-incidental renal cell carcinoma were 72, 48 and 41%, respectively, and those for incidental cancer patients were 100%. The survival of patients with incidental renal cell carcinoma was significantly better than that of non-incidental carcinoma patients (p < 0.005). CONCLUSION: Our results suggest that the detection of incidental renal cell carcinoma will increase, and that the prognosis for renal cell carcinoma will improve. However, even in incidental renal cell carcinoma, careful long-term follow up may be necessary, since some tumors are comparatively large and exhibit vascular invasion. 相似文献
73.
The effects of poly anionic-electrolyte (ammonium polyacrylate, PAA) as a dispersant on two kinds of ZrO2 (monoclinic and yttria-doped tetragonal zirconia) aqueous suspensions were examined by the measurements of-potential and viscosity, the sedimentation test and the determination of the wet point and flow point of the powders. Additions above 2.5 wt% PAA to zirconia gave a negative high-potential above –30 mV, and then –45 and –30 mV were obtained for monoclinic and tetragonal zirconia above 5 wt% PAA, respectively. A high negative-potential above –30 mV was retained with 5 wt% PAA for a change in pH over a wider range (pH 6 to 10 for monoclinic ZrO2, 7 to 9 for tetragonal ZrO2) in comparison to that of ZrO2 without dispersant. The increase of the-potential resulted in a decrease in the viscosity. The evaluation of dispersion by the sedimentation test was correlated well with the value of-potential and the viscosity of the suspensions. The presence of native positive charge of monoclinic and tetragonal zirconia powders required an excess amount of PAA to attain dispersion of the suspension. There was a small difference in the least amount of PAA required to attain good dispersion between monoclinic and tetragonal ZrO2. The difference was also indicated by changes of the flow point on PAA addition. Addition of 0.1% PAA to monoclinic ZrO2 and 0.25 wt% to tetragonal ZrO2 gave a maximum value of the flow point, whereas the positive-potential fell to zero. Measurement of the flow point was a simple and useful technique for rapid evaluation of a required amount of dispersant for ZrO2 suspensions. 相似文献
74.
We have measured the quenching rate of the Na 3P level and the doublet mixing rates of the Na 3P(3/2) and 3P(1/2) levels in a propane-air flame at atmospheric pressure. To obtain these rates, subnanosecond time-resolved fluorescence measurements were made using a mode-locked dye laser and the time-correlated single-photon counting method. Our results are 1.4 x 10(9) s(-1) for the quenching rate and 3.0 x 10(9) s(-1) for the 3P(3/2) --> 3P(1/2) mixing rate. 相似文献
75.
The recent publication of Binary Alloy Phase Diagrams,2nd ed, [90Mas] and our extensive screening of phase diagram graphics
for this edition has revealed many phase diagram features, which while not explicitly violating phase diagram rules, are to
a lesser or greater extent unlikely to represent thermodynamically acceptable conditions. In two previous papers, several
thermodynamically improbable features or boundaries in binary phase diagrams were pointed out [91Oka2], and some unlikely
thermodynamic models were shown to be unrealistic, or in error [91Okal]. In the present paper, we discuss some of the unlikely
features in more detail in order to develop a set of guidelines that may be useful for checking future proposed phase diagram
boundaries, or some specific phase diagram features resulting from both experimental and theoretical work, including also
phase diagram assessments. 相似文献
76.
77.
I. Hama T. Okamoto E. Hidai K. Yamada 《Journal of the American Oil Chemists' Society》1997,74(1):19-24
For the purpose of estimating the reaction mechanism of the direct ethoxylation of a fatty ester in the presence of an Al-Mg
composite oxide catalyst, a labeled fatty methyl ester C11H23CO18OCH3 containing 18O isotope was synthesized and directly ethoxylated. The product was evaluated by gas chromatography-mass spectrometry (GC-MS).
The GC-MS spectra showed that the 18O isotope label was present only in the methoxy group at the molecular end of the ethoxylated fatty methyl ester. This supports
the reaction mechanism of coordination anionic polymerization where the bond between the acyl and methoxy groups of the fatty
methyl ester molecule was broken, caused by the bifunctional effect of the acid-base active sites; an intermediate chemisorption
species was formed; and then ethylene oxide was addition-polymerized sequentially, in parallel. 相似文献
78.
W. R. Vogler A. C. Olson S. Okamoto M. Shoji R. L. Raynor J. F. Kuo W. E. Berdel H. Eibl J. Hajdu H. Nomura 《Lipids》1991,26(12):1418-1423
Alkyl lysophospholipids have been shown to be cytooxic to a number of neoplastic tissues. One, ET-18-OCH3, has been used to selectively purge leukemic cells from mixtures with normal marrow progenitor cells,in vitro andin vivo. We have measured the 50% inhibitory (IC50) effect of a series of ether, lipids (EL) on leukemic cells (HL60, K562, Daudi, KG-1, KG-1a) and normal marrow progenitor
cells. Cells were incubated with varying concentrations of EL for 4 hr and assayed for viability, [3H]thymidine incorporation and clonogenicity in semi-solid media. The effect on protein kinase C (PKC) activity was assayed
for each compound. Compounds tested included three glycerophosphocholine analogs-ET-18-OCH3, ET-16-NHCOCH3, and BM 41.440. In addition, a lipoidal amine, CP 46665, an ethyleneglycolphospholipid, AEPL, and four single chain alkylphosphocholine
analogs, HePC2, HePC3, HePC4 and HePC6 were also tested. During the period of incubation, the cells remained viable (>70%) as judged by trypan blue dye exclusion.
The glycerophosphocholines were the most active and showed the highest therapeutic index. The lipoidal amine was active, but
toxic to normal marrow progenitor cells. The ethyleneglycolphospholipid was active against HL60, but not against the other
cell lines. The single chain alkylphosphocholine analogs were less active. All of the compounds inhibited PKC activity; however,
the glycerophosphocholines were the most inhibitory.
Based on a paper presented at the Third International Conference on Platelet-Activating Factor and Structurally Related Alkyl
Ether Lipids, Tokyo, Japan, May 1989. 相似文献
79.
80.
α,β,β-Trifluoroethylenesulfonyl fluoride (TFESF) was grafted onto polyethylene (PE) film by a simultaneous-irradiation method. The influences of the grafting conditions were analyzed kinetically. The dependencies of the grafting rate on the dose rates and monomer concentrations ranging from 10 to 75% were found to be of 1 and 0 order, respectively. The overall activation energy for the graft polymerization was 2.05 × 104 J/mol. The grafting rate was found to be independent of the film thicknesses ranging from 25 to 100 μm. 相似文献